Hertel K008450AS Spiral Flute Tap 3/8-16 Unc Bottoming Hss

Product Description

The HERTEL K008450AS is a spiral flute tap designed to cut clean internal threads in blind holes where chips must be evacuated away from the cutting zone. Built from high-speed steel with an H3 thread limit, this tap produces 3/8-16 UNC right-hand threads to a 3B class of fit — a tolerance class suited for general-purpose fastener applications requiring moderate thread engagement and reliable fit. The bottoming chamfer style allows threading to the bottom of a blind hole, making it the right choice when full thread depth is required close to a hole's end. Overall length is 2-15/16 inches, and the fast-helix flute design at 52 degrees efficiently moves chips up and out of the hole.

This tap is used in machining, maintenance, and repair operations across manufacturing, fabrication, and industrial service environments. It is appropriate for tapping ferrous and non-ferrous materials in applications where blind-hole threading is required and chip packing is a concern. The 3/8-16 UNC thread form is one of the most common coarse-thread sizes in North American mechanical assembly. Licensed machinists, toolroom technicians, and skilled maintenance trades are the typical users. It is suited for use in CNC tapping cycles, turret lathes, drill presses, and hand-tapping fixtures where right-hand spiral flute geometry is specified.

Key Features

• Bottoming chamfer allows threading to near the bottom of a blind hole
• 52-degree fast-helix flute angle evacuates chips upward out of the cut zone
• H3 thread limit provides controlled oversize tolerance for plated or tight-fit applications
• 3B class of fit meets general-purpose UNC thread tolerance requirements
• High-speed steel construction offers toughness across a broad range of workpiece materials
• Right-hand flute direction and right-hand thread — standard for conventional tapping operations

Compatibility

Designed as a direct-use spiral flute tap for 3/8-16 UNC blind-hole threading applications. Compatible with standard tap holders and quick-change tapping chucks accepting the appropriate tap shank size.

Installation Notes

This tap is installed by qualified machinists or maintenance technicians using appropriate tap holders, collets, or tapping heads rated for the shank size. Always ensure the workpiece is securely fixtured and the spindle is set to the correct RPM and feed rate for the material being tapped before beginning the cycle. For hand tapping, use a calibrated tap handle and apply cutting fluid appropriate for the workpiece material. Inspect the tap for chipping or wear before each use — a damaged tap should be removed from service immediately to prevent thread damage or tap breakage in the hole.